Method, apparatus, and system of providing sensor-based tactile feedback

ABSTRACT

A method, system, and apparatus for providing feedback about firing on blueforce personnel are provided. A blueforce soldier is armed with a weapon that has one or more weapon sensors. The weapon sensors may provide information about a direction of fire and a firing state of the weapon. A blueforce-injury-possibility calculator may determine the direction of fire, the firing state, and an injury zone of the weapon based on the information from the weapon sensors. The blueforce-injury-possibility calculator may receive location information about one or more blueforce personnel. The blueforce-injury-possibility calculator may then determine a blueforce-injury possibility based on the injury zone and the location information. Tactile feedback may be provided to the blueforce soldier based on the blueforce-injury possibility. The tactile feedback may be provided via a tactile-feedback suit.

FIELD OF THE INVENTION

This invention generally relates to feedback to avoid friendly firecasualties, and specifically to providing tactile feedback when a weaponis trained on friendly personnel.

BACKGROUND

Soldiers are frequently at risk of injury or death in battle.Unfortunately, some soldiers are injured or killed due to fire fromfriendly forces, herein referred to as “blueforce” fire. Blueforce firemay come from a variety of weapons, including rifles, artillery pieces,and missiles. The resulting casualties both scar the soldier and drainthe morale of friendly forces and the soldier's family.

FIG. 1 is an example scenario where blueforce-fire casualties couldresult. In the scenario of FIG. 1, two blueforce soldiers 110 and 120and three non-blueforce persons 130, 140, and 150 are shown near twobuildings 160 and 170 and a blueforce-unit operation area 180. A “unitoperation area” is a geographic location where a force unit, such as aplatoon or company, is deployed. Blueforce soldier 110 is shown with aweapon 112 aimed away from other blueforce personnel, but blueforcesoldier 120 is shown with a weapon 122 aimed in the general direction ofblueforce soldier 110 and blueforce-unit operation area 180.

In this scenario, blueforce soldier 120 may be unaware of blueforcesoldier 110 as building 160 blocks the view of blueforce soldier 120.The building 160 may also partially block the view blueforce soldier 120has of blueforce-unit operation area 180. As such, if blueforce soldier120 is startled by a non-blueforce person 130, 140, 150 or by an eventin either building 160 or 170 (e.g., an unexpected person exiting abuilding or an explosion) or if weapon 122 malfunctions in a fashion tofire as aimed, a blueforce-fire casualty could result.

Various schemes have been proposed to provide notifications or feedbackabout the possibility of friendly fire. Notification of friendly forcesthat depend on visual indicators alone may force a soldier to move hisor her eyes to the visual indicator. Requiring a soldier to move his orher eyes may adversely affect the performance of the soldier, such aswhen aiming a weapon or driving a vehicle. Notifications of friendlyforces that depend on audible indicators alone may also be hazardous insome situations, such as when an audible indicator alerts enemies to thelocation of the soldier. In some situations, visible and/or audibleindicators may be difficult or even impossible for the soldier todetect, such as during a live-fire exercise or a battle.

SUMMARY

Embodiments of the present application include a method, system, andapparatus for providing feedback to blueforce personnel.

A first embodiment of the invention provides a method for providingfeedback to a blueforce soldier. The blueforce soldier is armed with aweapon. A state of the weapon is determined. One or more blueforcepersonnel are located. A blueforce-injury possibility is determined,based on the state of the weapon and the locations of the one or moreblueforce personnel. Feedback is determined, based on the determinedblueforce-injury possibility. The determined feedback is provided to theblueforce soldier.

A second embodiment of the invention provides a blueforce-injurypossibility calculator. The blueforce-injury possibility calculator hasa user interface, a sensor interface, a processor, data storage, andmachine-language instructions. The user interface includes at least onetactor. The sensor interface receives weapon-state information. Theweapon-state information includes a direction of fire of the weapon anda firing-state of the weapon. The machine-language instructions arestored in the data storage and are executable by the processing unit toperform functions. The functions include determining an injury zone ofthe weapon, based on the weapon-state information, locating one or moreblueforce personnel, determining a blueforce-injury possibility, basedon the injury zone and the locations of the one or more blueforcepersonnel, determining feedback based on the determined blueforce-injurypossibility, and providing the determined feedback via the at least onetactor.

A third embodiment of the invention provides a system. The systemincludes a weapon, a location system, a tactile-feedback suit, and ablueforce-injury calculator. The weapon includes at least one weaponsensor. The tactile-feedback suit includes at least one tactor. Theblueforce-injury possibility calculator is configured to: (i) receiveweapon-state information from the at least one weapon sensor, (ii)receive locations of blueforce personnel from the location system, (iii)determine an injury zone and a state of the weapon based on theweapon-state information, (iv) determine tactile feedback, based on thedetermined injury zone, the determined state of the weapon, and thereceived locations of blueforce personnel, and (v) provide thedetermined tactile feedback via the at least one tactor.

BRIEF DESCRIPTION OF THE DRAWINGS

Various examples of embodiments are described herein with reference tothe following drawings, wherein like numerals denote like entities, inwhich:

FIG. 1 is an example scenario where blueforce-fire casualties couldresult;

FIG. 2 is a block diagram showing an exampleblueforce-injury-possibility calculator and system, in accordance withembodiments of the invention;

FIG. 3 is an example rifle with weapon sensors, in accordance withembodiments of the invention;

FIG. 4A shows an example of a blueforce-soldier with a weapon system andan injury zone of the weapon system, in accordance with embodiments ofthe invention;

FIG. 4B shows another example of a blueforce-soldier with a weaponsystem and an injury zone of the weapon system, in accordance withembodiments of the invention;

FIG. 5 is an example computing device, in accordance with embodiments ofthe invention;

FIG. 6 is an example tactile-feedback suit, in accordance withembodiments of the invention; and

FIG. 7 is a flowchart depicting an example method, in accordance withembodiments of the invention.

DETAILED DESCRIPTION

The instant application describes use of feedback mechanisms, includingtactile feedback, to avoid friendly fire casualties. A blueforce soldiermay be armed with a weapon that has one or more weapon sensors. Theweapon sensors may provide information about a direction of fire and afiring state of the weapon. The direction of fire may be used todetermine an injury zone, or zone of possible harm to other blueforcepersonnel. The firing state of the weapon may indicate if the weapon canharm other blueforce personnel. For example, the firing state of theweapon may be “unable to fire” if a safety of the weapon is engagedand/or if the weapon is unloaded. Otherwise the firing state of theweapon may be “able to fire”.

The blueforce soldier may have a blueforce-injury-possibilitycalculator. The blueforce-injury-possibility calculator may determinethe direction of fire, the firing state, and the injury zone of theweapon, based on the information from the weapon sensors. Theblueforce-injury-possibility calculator may receive location informationabout one or more blueforce personnel. The blueforce-injury-possibilitycalculator may then determine a blueforce-injury possibility based onthe injury zone and the location information. The blueforce-injurypossibility may be zero if no blueforce personnel may be harmed by theweapon and may be non-zero if one or more blueforce persons may beharmed by the weapon (i.e., located within the injury zone of the weaponwith a firing state of “able to fire”).

The blueforce-injury-possibility calculator may provide output in theform tactile feedback, including vibrotactile feedback, to the blueforcesoldier if the blueforce-injury possibility is non-zero. The terms“output” and “feedback” are interchangeably used in this application.

Tactile feedback may effectively convey information. In particular, theuse of vibrations as tactile feedback or “vibrotactile feedback” may beeffective. Cholewiak and Collins indicate that tactile feedback patternswith low “communality” or few areas on the skin where feedback is commonbetween patterns can be effectively distinguished. Roger W. Cholewiakand Amy Collins, “Vibrotactile Pattern Discrimination and Communality atSeveral Body Sites”, Perception and Psychophysics, Vol. 57, No. 5, pp.724-37, 1995. The use of more tactors may decrease the communality ofthe vibrotactile patterns provided and consequently increase theeffectiveness of determining the pattern.

Vibrotactile feedback may be provided without requiring a person toshift their eyes to look at an indication, such as when visual feedbackis provided. Further, vibrotactile feedback may be provided withoutcausing light or sound emissions that could be seen or heard,respectively, by another person. Vibrotactile feedback may be felt instimulus-rich environments, such as a battlefield or during a policeraid, where visual and/or aural feedback may not be readily detected.One example of a wearable vibrotactile feedback system is manufacturedby Anthrotronix, Inc. of Silver Spring, Md.

Vibrotactile feedback may be provided by one or more “tactors” which aredevices designed to provide impulses, typically vibrations, to the skinof a user. An example tactor is the “C-2 Tactor” offered by EngineeringAcoustics, Inc. of Casselberry, Fla. Unlike the other senses, thesensory inputs for the sense of touch are scattered throughout the body.Therefore, tactors may be attached to a garment, such as a uniform ortactile-feedback suit, to provide tactile feedback. A vibrotactilefeedback system using several tactors is described in Aaron Bloomfieldand Norman I. Badler, “A Low Cost Tactor Suit for VibrotactileFeedback”, University of Pennsylvania Department of Computer andInformation Science, Jan. 1, 2003, which is entirely incorporated hereinby reference.

Varying levels and locations of tactile stimulation may be provided astactile feedback. For example, a relatively high amplitude and/or highfrequency vibrotactile pattern may indicate a nearby blueforce person orpersons, whereas a lower amplitude and/or frequency vibrotactile patternmay indicate more distant blueforce person(s). Other forms of tactilefeedback beyond vibrotactile feedback may be used as well. For examples,mild (and/or varying levels of) electrical shocks, chemical feedback,direct nerve stimulus, temperature changes, pressure, and/or painfultactile feedback may be used.

An Example Blueforce-Injury Possibility Calculator

Turning to the figures, FIG. 2 is a block diagram 200 showing an exampleblueforce-injury-possibility calculator 240 connected and receivinginputs from a blueforce-location server 210, weapon-state informationsource 220, and a blueforce-command source 230 as inputs, and providingas possible outputs tactile output 250, aural output 260, and visibleoutput 270, in accordance with embodiments of the invention. An examplecomputing device that may be utilized as a blueforce-injury-possibilitycalculator is described below with reference to FIG. 5.

The blueforce-injury-possibility calculator 240 may communicate withblueforce-location server 210 about the location of one or moreblueforce persons. An example blueforce-location server is the GlobalPersonnel Recovery System (GPRS) provided by Innovative Solutions,International of Vienna, Va. However other blueforce-location serversare available as well. The blueforce-location server 210 may comprisemultiple physical devices as well, such as multiple processors each ofwhich is performing as a server and/or each processor performing one ormore server-related tasks.

The blueforce-location server 210 may provide location informationgathered from location devices worn or carried by each blueforce person.Location information may be gathered from one or more location devicesmounted on a vehicle, such but not limited to a car, personnel carrier,or tank. The location devices may use one or more location techniques,such as but not limited to techniques based on Global Positioning System(GPS) technology, triangulation of radio waves, and/or dead reckoning. Alocation device may provide an update of the location of one or moreblueforce persons periodically, as requested, or using some other updatestrategy. The blueforce-location server 210 may provide locationinformation periodically, upon request, and/or using some otherstrategy, to blueforce-injury-possibility calculator 240.

Each location device may provide one or more location notifications toindicate a location. The one or more location notifications also mayindicate an identifier of a blueforce person (e.g., serial number), anidentifier of a unit of the blueforce person (e.g., Company A, 3^(rd)Platoon), and/or time/date information. And other information may bepart of a location notification as well.

The blueforce-injury-possibility calculator 240 may be equipped with alocation device. As such, the blueforce-injury-possibility calculator240 may provide location information, including location notifications,to the blueforce-location server 210. The location information providedby the blueforce-injury-possibility calculator 240 may enable theblueforce-location server to track the location of the soldier or otheruser of the blueforce-injury-possibility calculator 240.

The blueforce-location server 210 may provide location information ofindividual blueforce persons, such as the blueforce soldiers shown inFIG. 1, and/or blueforce units, such as the blueforce-unit operationarea also shown in FIG. 1. The blueforce-location server 210 may providelocation information about blueforce units by determining a unitoperation area for the blueforce unit based on the locationnotifications received from soldiers in the blueforce unit. For example,if an infantry company is deployed at a given area, locationnotifications from one or more soldiers in the infantry company may bereceived from the given area. The blueforce-location server 210 and/orthe blueforce-injury-possibility calculator 240 may determine that thegiven area is an operation area of the infantry company. One process todetermine the given area is an operation area is (i) determine thenumber of soldiers assigned to the unit (e.g., the infantry company) inthe given area, (ii) compare the number of soldiers to a threshold, and(iii) determine the given area is an operation area if the number ofsoldiers exceeds the threshold. Other processes for determining anoperation area are possible as well.

The blueforce-location server 210 and/or theblueforce-injury-possibility calculator 240 may maintain locationinformation about multiple blueforce units. The blueforce-locationserver 210 may maintain location information about blueforce personnelacross service boundaries (e.g., both Army and Marine units), acrosscommand boundaries, and/or across national boundaries (e.g., provideinformation about both United States and allied troops operating in thesame area). Also, the blueforce-injury-possibility calculator 240 mayreceive location information from multiple blueforce-location servers210 and determine location information from some or all of theblueforce-location servers 210. In particular, theblueforce-injury-possibility calculator 240 may filter locationinformation based on geographic location, such as determining thelocations of all blueforce personnel within 2000 meters of theblueforce-injury-possibility calculator 240. Theblueforce-injury-possibility calculator 240 may determine its ownlocation via information from one or more of the blueforce-locationservers 210 and/or via a location device aboard theblueforce-injury-possibility calculator 240.

The blueforce-injury-possibility calculator 240 may receive weapon-stateinformation from one or more weapon-state information sources 220. Theweapon-state information source 220 may provide information about a typeof a weapon, a direction of fire of the weapon, and a state of theweapon. An example weapon capable of including a weapon-stateinformation source 220 is described below with reference to FIG. 3.

The blueforce-injury-possibility calculator 240 may receive input from ablueforce-command source 230. The blueforce-command source 230 maycommunicate information from the chain of command of the user of theblueforce-injury-possibility calculator 240. For example, theblueforce-command source 230 may provide information aboutblueforce-unit operations or intelligence about enemy movements.

The blueforce-command source 230 may provide commands to theblueforce-injury-possibility calculator 240. The commands may bedirected to one or more blueforce-injury-possibility calculators 240,such as commands directed to a particular blueforce-injury-possibilitycalculator 240 (i.e., to a particular soldier), to allblueforce-injury-possibility calculators 240 in a given geographicalarea, and/or all blueforce-injury-possibility calculators 240 associatedwith particular unit(s) (e.g., all blueforce-injury-possibilitycalculators associated with Bravo Company). In particular, theblueforce-command source 230 may provide commands about output optionsof the blueforce-injury-possibility calculator 240. For example, theblueforce-command source 230 may provide commands to enable tactileoutput 250 and/or inhibit aural output 260 from allblueforce-injury-possibility calculators 240 in a blueforce-unitoperation area.

The blueforce-injury-possibility calculator 240 may communicate with theentities shown in FIG. 2 via a network. While the blueforce-locationserver 210, the weapon-state information source 220, and theblueforce-command source 230 are described as “inputs” above, they mayalso receive information from the blueforce-injury-possibilitycalculator 240 as well. For example, the blueforce-location server 210and/or the blueforce-command source 230 may receive input about aweapon-state via the blueforce-injury-possibility calculator 240. Asanother example, the weapon-state information source 220 may receiveinput from the blueforce-injury-possibility calculator 240 to control aweapon (e.g., engage a safety switch of the weapon).

Many other types of information may be passed from theblueforce-injury-possibility calculator 240 to the blueforce-locationserver 210, the weapon-state information source 220, and/or theblueforce-command source 230 as well. For example, information may bepassed to the blueforce-injury-possibility calculator about thelocations of special features (particularly non-military) of a location,such as refugee camps, locations of villages/towns, culturally sensitivesites, neutral/no-fire zones, locations where civilians may be wanderingunexpectedly (e.g., campgrounds or national parks), or gatherings ofpeople. The blueforce personnel may then attempt to accommodate thenon-military features of the location, such as changing a firing rate ofa weapon (i.e., change to single shot instead of full automatic whilenear a refugee camp), changing a direction of travel of the blueforcepersonnel, and/or change the choice weapons and/or ammunition used whileat or near those locations.

The blueforce-injury-possibility calculator 240 may use anetwork-communication interface, such as described below with respect toFIG. 5, to communicate with the blueforce-location server 210, theweapon-state information source 220, the blueforce-command source 230,and the output devices 250-270 shown in FIG. 2.

The blueforce-injury-possibility calculator 240 may provide one or moreoutputs. The one or more outputs may indicate the possibility of harmingone or more blueforce personnel, as well as an indication of potentialharm to the one or more blueforce personnel. FIG. 2 showsblueforce-injury-possibility calculator 240 connected to tactile output250, aural output 260, and visible output 270. An example tactile output250 is a tactile-feedback suit, which is described below with referenceto FIG. 5.

The aural output 260 may provide sounds, such as tones, beeps,vocalizations, and other sounds, as directed by theblueforce-injury-possibility calculator 240. The aural output 260 may bea speaker or other device capable of producing sounds, such as describedbelow with reference to the output unit of FIG. 5.

The visible output 270 may provide visible indications, such asalphanumeric characters, shapes, colors, and other visible indications,as directed by the blueforce-injury-possibility calculator 240. Thevisible output 270 may be a LCD, LED, or other display capable ofproducing textual and/or graphical output, such as described below withreference to the output unit of FIG. 5.

Similarly, the tactile output 250, the aural output 260, and the visibleoutput 270 may provide input to the blueforce-injury-possibilitycalculator 240 as well, such as diagnostic information or additionalinformation depending on the exact type of output device(s) used (e.g.,a visible output device that also has a camera may provide video inputto the blueforce-injury-possibility calculator 240 or the aural output260 may comprise a microphone for speech input). Many other types ofinformation may be passed to the blueforce-injury-possibility calculator240 from the tactile output 250, aural output 260, and visible output270 as well.

As another output, the blueforce-injury-possibility calculator 240 mayprovide an indication of potential harm to one or more blueforcepersonnel that may be harmed by the user of theblueforce-injury-possibility calculator 240. For example, if theblueforce-injury-possibility calculator 240 determines that Private Pylemay harm Sergeant Hartmann, the blueforce-injury-possibility calculator240 used by Private Pyle may send an indication of potential harm toSergeant Hartmann. The indication of potential harm may include thesource of the harm (e.g., Private Pyle), the location of theblueforce-injury-possibility calculator 240 sending the indication,and/or a time of the indication. The blueforce-injury-possibilitycalculator 240 may send the indication of potential harm directly to ablueforce-injury-possibility calculator 240 used by blueforce personnelthat may be harmed (i.e., assuming multiple blueforce-injury-possibilitycalculators are connected via a wired or wireless LAN/WAN) or indirectlyvia a network entity, such as a blueforce-location server 210 or theblueforce-command source 230.

An Example Weapon

FIG. 3 is an example weapon system 300 with weapon sensors 350, 360, and370, in accordance with embodiments of the invention. The example weaponsystem 300 is shown in FIG. 3 is a rifle with a stock 310, a barrel 320,a muzzle 330 of the barrel 320, and a trigger 340. The rifle may beoperated by a soldier or other user by loading the rifle with one ormore rounds (bullets), holding the stock 310 next to the shoulder of theuser, aiming the rifle in the direction of the muzzle 330, and pullingthe trigger 340 to fire the loaded rounds.

The weapon system 300 may be equipped with a safety 342. The safety 342may be engaged or not engaged. When the safety 342 is engaged, theweapon system 300 may be prohibited from firing even if the weaponsystem 300 is loaded and the trigger 340 is pulled. However, when thesafety 342 is not engaged, the weapon system 300 may be able to fireloaded rounds when the trigger 340 is pulled.

The weapon-state sensor 350 may be provide data used to determine a“firing state” of the weapon system 300. The firing state of the weaponsystem 300 is the ability of the weapon to immediately fire; e.g., thefiring state of the weapon system 300 may be “able to fire” or “unableto fire”. The firing state of the weapon system 300 may depend on thestate of the safety 342 and a number of rounds loaded into weapon system300. For example, the weapon system 300 may have a firing state of “ableto fire” if (a) the safety is not engaged and (b) one or more rounds areloaded in the weapon system. Otherwise, the firing state may be “unableto fire”. Other methods for determining and/or expressing the firingstate are possible as well. The weapon-state sensor 350 may provide datasuch as the state of the safety 342 and/or the number of rounds loadedin the weapon 300. The data provided by the weapon-state sensor 350 may,in addition or instead of the number of rounds, comprise aloaded/unloaded indicator of the weapon 300. The loaded/unloadedindicator may indicate “unloaded” if no rounds were loaded into theweapon 300 or indicate “loaded” if one or more rounds were loaded intothe weapon 300.

The weapon-state sensor 350 may also be able to determine if a round is“chambered” or loaded into the weapon system 300 and also ready forimmediate fire by the weapon system 300. In that case, the firing statemay be “able to fire” if (a) the safety is not engaged and (b) a roundis chambered. Otherwise, the firing state may be “unable to fire”. Useof a weapon-state sensor 350 that can determine when a round ischambered permits the distinction of a weapon system that is loaded butunable to fire since a round has not yet been chambered.

The direction of fire of the weapon system 300 may be determined basedon data from the back sensor 360 and/or front sensor 370. At any giventime, the back sensor 360 and the front sensor 370 may each providetheir current position. Preferably, the back sensor 360 and/or the frontsensor 370 each provide their current position using Global PositioningSystem (GPS) technology or a similar technology. The current position ofa sensor may be indicated in three dimensions using a coordinate system(e.g., a two or three dimensional Cartesian coordinate system), as alatitude, longitude, and elevation, via map coordinates, or by use ofanother way of indicating a current position. Timing information may beprovided with the current position information as well, e.g., indicatingthe position of a sensor at 1100 hours on Jun. 7, 2008. The location ofthe weapon system 300 may be determined to be the current position ofeither the front sensor 370 or the back sensor 360.

The back sensor 360 and/or the front sensor 370 may provide theirrespective current positions to a blueforce-injury-possibilitycalculator or similar device to determine the direction of fire of theweapon. For example, suppose the back sensor indicates a position of[10,10,10] in a given [x,y,z] coordinate system at a given time t andthe front sensor indicates a position of [10,12,10] in the same [x,y,z]coordinate system at time t. For example, a relative position of theweapon of [0,2,0] may be determined by subtracting the front sensorposition from the rear sensor position. The relative position of theweapon may indicate a direction of fire, e.g., the relative position of[0,2,0] indicating the weapon is aimed solely in the y-direction. Therelative position may be used to determine a targeting solution of theweapon, such as the azimuth, direction, and/or elevation values for theweapon. The relative position and/or the direction of fire may bedetermined by other means as well, such as, but not limited to, inertialsensors, accelerometers, electronic compasses, gyroscopes (includingring laser gyroscopes), and/or optical location devices.

The example weapon system 300 shown in FIG. 3 is a rifle, but otherweapon systems may utilize weapon sensors similarly. That is, othertypes of weapons may utilize one or more sensors to provide weapon-stateinformation (and thus act as a weapon-state information source 220). Forexample, similar sensors to the back sensor 360 and front sensor 370 (orthe same sensors) may be added to larger weapons, such as artillerypieces or missile launchers, to determine a direction of fire of thelarger weapon. A similar weapon-state sensor to weapon-state sensor 370may be used to determine if a shell is or is not loaded into such alarger weapon.

Examples of Injury Zones

FIG. 4A shows an example of a blueforce-soldier 400 with a weapon system410 and an injury zone 420 of the weapon system 410, in accordance withembodiments of the invention. An “injury zone” of a weapon system may bedetermined based on a direction of fire. FIG. 4A shows an injury zone420 with dashed lines and defined by a left extent 414, a right extent416, and an outer extent 418 oriented around a direction of fire (DOF)412. The direction of fire 412 may be determined as described above withreference to FIG. 3.

Once the direction of fire 412 is determined, the left extent 414 andright extent 416 of the injury zone 420 may be determined. The leftextent 414 and right extent 416 indicate the likely-leftmost directionof fire and likely-rightmost direction of fire, respectively, if theweapon system 410 is discharged when initially aimed along the directionof fire 412. That is, if the weapon system 410 is discharged while aimedalong the direction of fire 412, the discharged round will likely travelalong a path somewhere between the left extent 414 and the right extent416. The injury zone 420 may also depend on the location of the weaponsystem 410.

The left extent 414 and/or the right extent 416 of the injury zone 420may be determined with respect to one or more “weapon-system movement”angles. FIG. 4A shows the left extent 414 defined with respect to anangle of L° and the right extent 416 defined with respect to an angle ofR°. Note that the angle L° may or may not be the same as the angle R°.For example, L° may not be the same as R° if the blueforce-soldier 400tends to move the weapon system 410 to the left (or right) while firing.The angles L° and/or R° may also depend on the situation of theblueforce soldier 400; for example, L′ and/or R′ may be smaller when theblueforce soldier 400 is deployed with many other soldierssimultaneously (i.e., with his/her unit) as the risk of blueforce-fireinjuries has increased due to the higher density of blueforce personnel.

The angles L° and/or R° may further depend on meteorological conditions,such as temperature, humidity, and wind—for example, if a wind isblowing in the direction from the blueforce-unit operation area 440toward the blueforce soldier 434, a round fired from the weapon system410 may be blown in that wind toward the right extent and as such, R°may be greater than L°. Similarly, R° may be less than L° if the windblows in the direction from the blueforce soldier 434 toward theblueforce-unit operation area 440.

The outer extent 418 of the injury zone 420 may be the farthest distancefrom the muzzle of the weapon system 410 where a person may be injuredby a round fired from weapon system 410. The outer extent 418 may bebased on the type of the weapon system 410. For example, if the weaponsystem 410 may fire rounds that travel 1000 meters, the outer extent 418may be farther from the weapon system 410 than if the weapon system 410can fire rounds that travel 900 meters. The outer extent may be based onthe type of rounds fired by the weapon system 410. For example, if theweapon system 410 is loaded with rounds that may travel 700 meters, theouter extent 418 may be farther from the weapon system 410 than if theweapon system 410 is loaded with rounds that travel 650 meters.

The outer extent 418 may further depend on meteorological conditions,such as temperature, humidity, and wind. For example, if a wind isblowing in the direction from the blueforce-soldier 400 toward theblueforce soldier 434, a round fired from weapon system 410 may be blownin that wind farther than if no wind was blowing, and as such, the outerextent 418 may be increased due to the wind. Similarly, the outer extent418 may be decreased when the wind blows in the direction from theblueforce soldier 434 toward blueforce soldier 400 FIG. 4B shows anotherexample of a blueforce-soldier 450 with a weapon system 460 and aninjury zone 470 of the weapon system 460, in accordance with embodimentsof the invention. The determination of the injury zone may depend on thetype of weapon system. FIG. 4B shows a blueforce soldier 450 operating amortar as the weapon system 470. The weapon system 460 may fire roundsthat generally land in a circular or elliptical region some distancefrom the weapon system 460. FIG. 4B shows the injury zone 470 as acircular region some distance from weapon system 460. The injury zone470 may be determined by a mathematical model, such as the well-knownballistics equations of motion, based on the direction of fire orazimuth, elevation, and location of the weapon system 470. Also, asdescribed above with respect to FIG. 4A, the injury zone 480 may bedetermined based on the type of weapon system and/or the types of roundsfired by the weapon system. For example, if the weapon system 470 is anartillery piece or a tank, the injury zone may have a different shapeand/or size than the injury zone for a rifle or a mortar. Also, the sizeand shape of the injury zone of the weapon system 470 may vary overtime. For example, if the weapon system 470 is firing rounds with moreexplosives than previously-fired rounds, the injury zone 480 may beenlarged and/or have a different shape compared to an injury zonedetermined for the previously-fired rounds.

A blueforce-injury possibility may be determined based on thelocation(s) of blueforce person(s) and/or the state of a weapon system.FIG. 4A shows a blueforce soldier 430 partially in the injury zone 420of the weapon system 410. As the blueforce soldier 430 is in the injuryzone 420, the blueforce soldier 430 may risk injury if the weapon system410 is fired, and thus the blueforce-injury possibility to the blueforcesoldier 430 may be non-zero. However, if the weapon state of the weaponsystem 410 is “unable to fire”, the blueforce-injury possibility to theblueforce soldier 430 may be zero. Also, the blueforce soldiers 420 and440 are not at risk of injury from weapon system 410 as they are outsidethe injury zone 420. Further, any blueforce personnel operating in theblueforce-unit operation area 450 are also outside the injury zone 420,and thus not at risk of injury from weapon system 410.

The determination of the blueforce-injury possibility may depend on oneor more settings, such as user settings, of theblueforce-injury-possibility calculator 240. One of the settings of theblueforce-injury-possibility calculator 240 may indicate a operationalmode to the blueforce-injury-possibility calculator 240. Exampleoperational modes are an “active” mode, a “blueforce-radar” mode, and/oran “inactive mode.” The active mode may indicate that theblueforce-injury-possibility calculator 240 determines theblueforce-injury possibility based on the injury zone and the firingstate of a weapon system. The blueforce-radar mode may indicate that theblueforce-injury possibility is based only on the injury zone of theweapon system—as such, while in blueforce-radar mode, theblueforce-injury possibility treats the weapon system as a pointer tolocate blueforce personnel. The weapon system can remain unloaded whilein blueforce-radar mode, as the firing state is ignored, and thus reducethe risk to blueforce personnel while the weapon system is maneuvered inan attempt to find blueforce personnel. The inactive mode may indicatethe blueforce-injury-possibility calculator 240 is not being used and sothe blueforce-injury-possibility calculator 240 may not provide anydetermination of the blueforce-injury possibility regardless of theinjury zone and/or the firing state.

For example, if the blueforce soldier 400 is using the blueforce-injurypossibility calculator mode in the active mode, theblueforce-injury-possibility calculator 240 provides feedback based on ablueforce-injury possibility to a user, including taking into accountthe firing state of a weapon system 410 of the blueforce soldier 400. Assuch, no feedback will be provided to the blueforce soldier 400 ifweapon system 410 is unloaded or has the safety engaged. However, whilein blueforce-radar mode, the blueforce-injury-possibility calculator 240does not take into account the firing state of the weapon system 410,and thus provides feedback to the blueforce soldier 400 based only onthe injury zone of the weapon system 410, enabling the blueforce soldier400 to locate the blueforce soldiers 430 and 432 by maneuvering theweapon system 410 while the weapon system 410 is not able to fire (e.g.,while weapon system 410 is unloaded or has the safety is engaged).

FIG. 4B shows a blueforce soldier 480 in the injury zone 470 of weaponsystem 460. Also, part of the blueforce-unit operation area 490 overlapsthe injury zone 470. Therefore, if the weapon system 460 fires, theblueforce soldier 480 and any blueforce personnel in the portion of theblueforce-unit operation area 490 that overlaps the injury zone 470 mayhave a non-zero blueforce-injury possibility.

An Example Computing Device

FIG. 5 is a block diagram of an example computing device 500, comprisinga processing unit 510, data storage 520, a user interface 530, and anetwork-communication interface 560, in accordance with embodiments ofthe invention. A computing device 500 may be a desktop computer, laptopor notebook computer, personal data assistant (PDA), mobile phone,embedded processor, or any similar device that is equipped with aprocessing unit capable of executing computer instructions thatimplement at least part of the herein-described method 700 of FIG. 7and/or herein-described functionality of a blueforce-injury-possibilitycalculator.

The processing unit 510 may include one or more central processingunits, computer processors, mobile processors, digital signal processors(DSPs), microprocessors, computer chips, and similar processing unitsnow known and later developed and may execute machine-languageinstructions and process data.

The data storage 520 may comprise one or more storage devices. The datastorage 520 may include read-only memory (ROM), random access memory(RAM), removable-disk-drive memory, hard-disk memory, magnetic-tapememory, flash memory, and similar storage devices now known and laterdeveloped. The data storage 520 comprises at least enough storagecapacity to contain machine-language instructions 522 and datastructures 524.

The machine-language instructions 522 and the data structures 524contained in the data storage 520 include instructions executable by theprocessing unit 510 and any storage required, respectively, to performsome or all of the functions of a herein-describedblueforce-injury-probability calculator, a blueforce location server, aweapon-state information source, a blueforce-command source, and/or toperform some or all of the procedures described in method 700.

The user interface 530 may comprise an input unit 540 and/or an outputunit 550. The input unit 540 may receive user input from a user of thecomputing device 530. The input unit 540 may comprise a keyboard, akeypad, a touch screen, a computer mouse, a track ball, a joystick,and/or other similar devices, now known or later developed, capable ofreceiving user input from a user of the computing device 500.

The input unit 540 may also comprise a location device. The locationdevice may determine the location of the computing device 500 via one ormore location technologies, such as Global Position System (GPS),triangulation of electromagnetic waves, dead reckoning, or by anotherlocation technology.

The output unit 550 may provide output to a user of the computing device500. The output unit 550 may comprise a visible output device 552, suchas one or more cathode ray tubes (CRT), liquid crystal displays (LCD),light emitting diodes (LEDs), displays using digital light processing(DLP) technology, printers, light bulbs, and/or other similar devices,now known or later developed, capable of displaying graphical, textual,and/or numerical information to a user of computing device 500. Theoutput unit 550 may alternately or additionally comprise one or moreaural output devices 554, such as a speaker, speaker jack, audio outputport, audio output device, earphones, and/or other similar devices, nowknown or later developed, capable of conveying sound and/or audibleinformation to a user of computing device 500. The output unit 550 mayalso comprise one or more tactile output devices 556, such as a tactor,a tactile buzzer, tactile cue, and/or other similar devices, now knownor later developed, capable of providing tactile information to a userof computing device 500. The output unit 550 may also comprise part orall of a tactile-feedback suit described below with reference to FIG. 6.

The network-communication interface 560 is configured to send andreceive data and may include a wired-communication interface and/or awireless-communication interface. The wired-communication interface, ifpresent, may comprise a wire, cable, fiber-optic link or similarphysical connection to a wide area network (WAN), a local area network(LAN), one or more public data networks, such as the Internet, one ormore private data networks, or any combination of such networks. Thewireless-communication interface, if present, may utilize an airinterface, such as an IEEE 802.11 (e.g., Wi-Fi) and/or IEEE 802.16(e.g., WiMax) interface to a WAN, a LAN, one or more public datanetworks (e.g., the Internet), one or more private data networks, or anycombination of public and private data networks.

An Example Tactile-Feedback Suit

FIG. 6 is an example tactile-feedback suit 600 shown with tactors 610and 620, a tactor belt 630, a display 640, and an earpiece 650 connectedto blueforce-injury-possibility calculator 240 in accordance withembodiments of the invention. The tactile-feedback suit 600 may providetactile stimulation or feedback to the wearer via one or more tactors.FIG. 6 shows the tactile-feedback suit 600 with two tactors 610 and 620.More or fewer tactors may be part of the tactile-feedback suit 600. Thetactors 610 and 620 are shown on the shoulders of the tactile-feedbacksuit 600. However, the tactile-feedback suit may have tactors on anyportion of the tactile-feedback suit 600, including (but not limitedto), the head, legs, arms, hands, trunk, back, sides, and/or feet of thetactile-feedback suit 600. Also, the tactors may be arranged in one ormore bands or belts, such as the tactor belt 630. FIG. 6 shows thetactile-feedback suit 600 as a separate suit, but the components of thetactile-feedback suit 600 may be part of or attached to another garment,such as a uniform, as well.

Each tactor may provide various levels of stimulation to the wearer ofthe tactile-feedback suit 600. Each tactor may be directed to providestimulation of varying frequencies, durations, amplitudes, and/or curveshapes (e.g., square waves or sinusoidal waves). The use of differentfrequencies, durations, amplitudes, and/or curve shapes may providetactile feedback about the relative locations of and/or risks toblueforce personnel. For example, a low-amplitude and/or low-frequencyburst of stimulation from one or more tactors may indicate thatblueforce personnel are relatively far away or are at low risk ofinjury. However, a high-amplitude and/or high-frequency burst ofstimulation may indicate blueforce personnel are relatively close and/orat high risk of injury. As another example, the duration of the burst ofstimulation may be tied to the duration of the risk to blueforcepersonnel; that is, the burst may last as long as blueforce personnelare at risk due to blueforce fire from the wearer of thetactile-feedback suit 600.

The use of tactors on various portions of the body may provideadditional feedback. For example, suppose the tactile-feedback suit 600has tactors on the front, back, and on each side. If blueforce personnelin front or behind the wearer of the tactile-feedback suit 600 are atrisk, the tactors on the front or the back, respectively, oftactile-feedback suit 600 may be activated to provide a burst ofstimulation. Similarly, if the blueforce personnel at risk are on theright (or left) of the wearer of the tactile-feedback suit 600, tactorson the right side (or the left side) may be activated.

Use of other types of tactile feedback beyond vibrotactile feedback maybe used with tactile-feedback suit 600. FIG. 6 shows thetactile-feedback suit with an electroshock unit 632. The electroshockunit 632 may be configured to provide electric shocks to the wearer ofthe tactile-feedback suit 600. As with tactors, one or more electroshockunits may be directed to provide electric shock stimulation of varyingfrequencies, durations, amplitudes, and/or curve shapes. Providing othertypes of tactile stimulation devices (i.e., other than tactors 610-620,tactor belt 630, and electroshock unit 632) with the tactile-feedbacksuit 600 may provide other types of tactile feedback to the wearer ofthe tactile-feedback suit 600, such as, but not limited to, chemicalfeedback, direct nerve stimulus, temperature changes, pressure, and/orpainful tactile feedback. Further, different types of tactile feedbackmay be provided depending on the situation, such as use of vibrotactilefeedback for relatively low risks to blueforce personnel and electricshocks and/or painful feedback for relatively high risks to blueforcepersonnel.

The tactile-feedback suit may provide support for visible and/or auralfeedback as well. Then, the blueforce-injury-possibility calculator 240may instruct tactile-feedback suit 600 to provide visible and/or auralfeedback in addition to tactile feedback. FIG. 6 shows thetactile-feedback suit 600 equipped with a display 640 and an earpiece650 for visible and aural feedback, respectively. The visible and/oraural feedback may provide additional information about the location ofblueforce personnel and/or units. Further, visible and/or aural feedbackmay be provided if the capacity for tactile feedback is reduced or zero,such as when the tactors 610 and 620 and/or tactor belt 630 areinoperable.

An Example Method for Providing Feedback to a Blueforce Soldier

FIG. 7 is a flowchart depicting an example method 700, in accordancewith embodiments of the invention. Method 700 provides feedback to ablueforce soldier armed with a weapon. It should be understood that eachblock in this flowchart and within other flowcharts presented herein mayrepresent a module, segment, or portion of computer program code, whichincludes one or more executable instructions for implementing specificlogical functions or steps in the process. Alternate implementations areincluded within the scope of the example embodiments in which functionsmay be executed out of order from that shown or discussed, includingsubstantially concurrently or in reverse order, depending on thefunctionality involved, as would be understood by those reasonablyskilled in the art of the described embodiments.

At block 710, a blueforce-injury-possibility calculator is initialized.The blueforce-injury-possibility calculator may be initialized based onuser settings. For example, the user of the blueforce-injury-possibilitycalculator may enable, disable, and/or adjust tactile, aural, and/orvisible feedback. The user settings may comprise feedback parameters.The feedback parameters may include the frequency, duration, amplitudeand/or curve shapes of tactile and/or aural feedback. The user settingsmay include a maximum value, a minimum value, and/or an enabled/disabledstatus for each feedback parameter. The user settings may indicate amode of the blueforce-injury-possibility calculator, such as an activemode, an inactive mode, and/or a blueforce-radar mode. For visiblefeedback, frequency, duration, color, and/or size user settings and/orfeedback parameters may be provided. Many other user settings and/orfeedback parameters are possible as well.

The feedback parameters and/or the user settings may be set by ablueforce-command source. The feedback parameters and/or the usersettings may be “locked”, that is, unable to be changed by the user ofthe blueforce-injury-possibility calculator. In particular, lockedfeedback parameters and/or user settings may be provided as commandsfrom the blueforce-command source to the user of theblueforce-injury-possibility calculator.

User settings and/or feedback parameters may be determined by one ormore algorithms. For example, a “location direction” algorithm may settactile feedback parameters to indicate a relative location of anyblueforce personnel in the injury zone of a weapon of the user of theblueforce-injury-possibility calculator. The location directionalgorithm may set: (a) tactile-duration feedback parameter(s) to providefeedback while the blueforce personnel are in the injury zone and (b)tactile-frequency and/or tactile-amplitude parameters to be proportionalto the distance to the blueforce personnel in the injury zone. Thelocation direction algorithm may make similar settings for aural and/orvisible feedback parameters as well. Another example is an algorithmthat generates tactile-feedback patterns via a number of tactors withlow communality and consequently increases effectiveness indistinguishing between the tactile-feedback patterns. Some or all of theherein-described user settings and/or feedback parameters may behardcoded as well.

At block 720, a state of a weapon is determined. The state of the weaponmay comprise a direction of fire. The direction of fire may bedetermined based on data from one or more weapon sensors attached to theweapon. In particular, the direction of fire may be determined bylocation data from a front location sensor and a rear location sensor. Arelative position of the weapon may be determined by subtractinglocation data from the front location sensor from location data from therear location data (or vice versa). The direction of fire may bedetermined based on the relative position of the weapon.

The state of the weapon may comprise an injury zone. The injury zone maybe based on the direction of fire of the weapon, the type of weapon,and/or the type of rounds used by the weapon. The size and/or shape ofthe injury zone may vary over time. The injury zone may be wedge-shaped,elliptical, circular, or of another shape altogether.

The state of the weapon may comprise a firing state of the weapon. Thefiring state of the weapon may be expressed as “able to fire” or “unableto fire”. The firing state may comprise a state of a safety of theweapon (e.g., engaged or not engaged) and/or a number of rounds loadedin the weapon system. The firing state may be determined based on datafrom one or more weapon sensors. The one or more weapon sensors mayprovide data on the state of the safety, the number of rounds loaded inthe weapon system and/or a loaded/unloaded indicator.

At block 730, one or more blueforce personnel are located. The blueforcepersonnel may be located by the blueforce-injury-possibility calculatorbased on location information received from one or moreblueforce-location servers. The blueforce-injury-possibility calculatormay filter the received location information, such as filtering thereceived location information based on the location of theblueforce-injury-possibility calculator.

At block 740, a blueforce-injury possibility is determined based on thestate of the weapon and the locations of the one or more blueforcepersonnel. One sequence of operations to determine the blueforce-injurypossibility is:

-   -   (i) Determine the firing state of the weapon. If the firing        state of the weapon is “unable to fire”, then the        blueforce-injury possibility may be determined to be zero as the        weapon cannot harm any blueforce personnel. Proceed on to        operation (ii) if the firing state of the weapon is “able to        fire”.    -   (ii) Determine the injury zone of the weapon.    -   (iii) Determine the location(s) of blueforce personnel.    -   (iv) Determine if the locations of any blueforce personnel are        partially or completely within the injury zone of the weapon. If        no blueforce personnel are within the injury zone of the weapon,        then the blueforce-injury possibility may be determined to be        zero. Proceed on to operation (v) if blueforce personnel are in        the injury zone of the weapon.    -   (v) Determine a non-zero blueforce-injury possibility. For        example, the blueforce-injury possibility to a blueforce person        may be proportional to the relative location of a blueforce        person and the weapon. The blueforce-injury possibility may be        determined based on stored data, such as a database or lookup        table. The stored data may be indexed by the relative location        of the blueforce person, the type of the weapon, and/or the type        of rounds loaded into the weapon.

Note that other sequences of operations may be used to determine theblueforce-injury possibility, including performing the above mentionedoperations in a different sequence.

At block 750, feedback is determined based on the determinedblueforce-injury possibility. For example, the frequency and/or theamplitude of the feedback (e.g., tactile feedback) may be directlyproportional to the blueforce-injury possibility. Also the curve shapeof the feedback may be determined based on the determinedblueforce-injury possibility, such as use of square-wave feedback if theblueforce-injury possibility exceeds a threshold and use ofsinusoidal-wave feedback if the blueforce-injury possibility does notexceed the threshold.

At block 760, the determined feedback is provided to the blueforcesoldier. The determined feedback may be provided via an output unitcomprising visible, aural, and/or tactile output devices. The tactileoutput device(s) may include one or more tactors and may include atactile-feedback suit. After performing block 760, the method 700 mayproceed to block 720. As such, if the state of the weapon and/or thelocations of blueforce personnel change, the determined feedback maychange between iterations of method 700.

Conclusion

Exemplary embodiments of the present invention have been describedabove. Those skilled in the art will understand, however, that changesand modifications may be made to the embodiments described withoutdeparting from the true scope and spirit of the present invention, whichis defined by the claims. It should be understood, however, that thisand other arrangements described in detail herein are provided forpurposes of example only and that the invention encompasses allmodifications and enhancements within the scope and spirit of thefollowing claims. As such, those skilled in the art will appreciate thatother arrangements and other elements (e.g. machines, interfaces,functions, orders, and groupings of functions, etc.) can be usedinstead, and some elements may be omitted altogether.

Further, many of the elements described herein are functional entitiesthat may be implemented as discrete or distributed components or inconjunction with other components, in any suitable combination andlocation, and as any suitable combination of hardware, firmware, and/orsoftware.

1. A method for providing feedback to a blueforce soldier armed with a weapon, comprising: determining a state of the weapon; locating one or more blueforce personnel; determining a blueforce-injury possibility based on the state of the weapon and the location of the one or more blueforce personnel; determining feedback based on the determined blueforce-injury possibility; and providing the feedback to the blueforce soldier.
 2. The method of claim 1, wherein the state of the weapon comprises a state of a safety of the weapon.
 3. The method of claim 1, wherein the state of the weapon comprises a direction of fire of the weapon.
 4. The method of claim 1, wherein providing the feedback to the blueforce soldier comprises providing tactile feedback to the blueforce soldier.
 5. The method of claim 4, wherein providing tactile feedback to the blueforce soldier comprises providing tactile feedback to the blueforce solder about the location of the one or more blueforce personnel.
 6. The method of claim 1, wherein determining feedback comprises determining a level of feedback to be provided based on a comparison of the blueforce-injury possibility to at least one blueforce-injury possibility threshold.
 7. The method of claim 6, wherein determining a level of feedback to be provided comprises determining no feedback is to be provided based on determining the blueforce-injury possibility is less than a first blueforce-injury possibility threshold.
 8. The method of claim 7, wherein determining a level of feedback to be provided comprises determining tactile feedback is to be provided based on determining the blueforce-injury possibility is greater than a first blueforce-injury possibility threshold.
 9. The method of claim 8, wherein the determined level of tactile feedback to be provided is proportional to the blueforce-injury possibility.
 10. A blueforce-injury possibility calculator, comprising: a user interface; a sensor interface for receiving weapon-state information, wherein the weapon-state information comprises a direction of fire of a weapon and a firing-state of the weapon; a processor; data storage; and machine-language instructions stored in the data storage and executable by the processing unit to perform functions including: determining an injury zone of the weapon based on the weapon-state information, locating one or more blueforce personnel, determining a blueforce-injury possibility based on the injury zone and the locations of the one or more blueforce personnel, determining feedback based on the blueforce-injury possibility, and providing the feedback.
 11. The blueforce-injury-possibility calculator of claim 10, wherein the weapon-state information comprises a direction of fire of the weapon.
 12. The blueforce-injury-possibility calculator of claim 10, wherein the weapon-state information comprises a type of weapon.
 13. The blueforce-injury-possibility calculator of claim 10, wherein the user interface comprises a tactor.
 14. The blueforce-injury-possibility calculator of claim 10, wherein determining a blueforce-injury possibility depends on a mode of the blueforce-injury possibility calculator.
 15. The blueforce-injury-possibility calculator of claim 14, wherein the mode of the blueforce-injury-possibility calculator comprises a blueforce-radar mode and an active mode, and wherein determining the blueforce-injury possibility comprises: (1) determining a blueforce-injury possibility based on the injury zone while the blueforce-injury-possibility calculator is in the blueforce-radar mode and (2) determining a blueforce-injury possibility based on the injury zone and a firing state of the weapon while the blueforce-injury-possibility calculator is in the active mode.
 16. A system, comprising: a weapon comprising at least one weapon sensor; a location system; a tactile-feedback suit comprising at least one tactor; and a blueforce-injury possibility calculator configured to: (i) receive weapon-state information from the at least one weapon sensor, (ii) receive locations of blueforce personnel from the location system, (iii) determine an injury zone and a state of the weapon based on the weapon-state information, (iv) determine tactile feedback to be provided based on the injury zone, the state of the weapon, and the locations of blueforce personnel, and (v) provide the tactile feedback via the at least one tactor.
 17. The system of claim 16, wherein the at least one weapon sensor comprises a weapon-state sensor.
 18. The system of claim 17, wherein the weapon-state information from the weapon-state sensor comprises information about a safety of the weapon.
 19. The system of claim 17, wherein the at least one weapon sensor comprises at least one global positioning system (GPS) sensor.
 20. The system of claim 19, wherein the weapon-state information comprises information about a direction of fire of the weapon from the at least one GPS sensor. 